This invention relates to a method and device for reading characters on a document and more particularly but not by way of limitation to a method and device for reading unknown magnetic or optical characters on bank documents. The device measures the unknown character's waveform amplitude along timed intervals and determining that each measurement is within a predetermined acceptable amplitude range at each interval for an ideal character.
Heretofore there have been various types of character recognition devices such as the character recognition system described in British Pat. No. 1,015,886. Also there are various types of character reader systems described in U.S. Pat. No. 3,503,043 to Brass, U.S. Pat. No. 3,521,236 to Parks et al, U.S. Pat. No. 3,585,588 to Hardin et al, U.S. Pat. No. 3,847,346 to Dolch and U.S. Pat. No. 3,930,230 to Stephens. None of the above patents describes nor discloses a method or device which defines acceptable amplitude tolerance ranges at each phase point along the waveform of an unknown character to be sensed in determining for character recognition. The advantages and unique features of the present invention are described as follows.